Shoring jack

ABSTRACT

1. A JACK SCREW ASSEMBLY FOR USE IN A SHORING SYSTEM COMPRISING A HOLLOW JACK STAFF HAVING A THREADED PORTION, A NUT ON THE THREADED PORTION FOR VERTICAL TRAVEL THEREOVER, A LOADBEARING SLEEVE BEARING AGAINST THE NUT, AND EXTENDING OVER THE JACK STAFF TO THE END THEREOF, AND AN INTERNAL SHAFT FIXED TO THE SLEEVE BUT EXTENDING VERTICALY INTO THE JACK STAFF A DISTANCE GREATER THAN THE LENGTH OF THE THREADED PORTION.

United States Patent [1 1 Kutchai [451 Nov.26,1974

[ SHORING JACK [76] Inventor: Jacob H. Kutchai, 630 Merrick,

Detroit, Mich. 48202 22 Filed: Mar. 29, 1972' 21 Appl.No.:239,099

Related U.S. Application Data [62] Division of Ser. No. 65,137, Aug. 19,1970.

Primary ExaminerJacob Shapiro A ttorney, Agent, or Firm-Thomas N. Young[5 7] ABSTRACT A shoring system of the type having one or moreverfically a rranged frame sections and telescopic extension membersextendable therefrom. A frame brace bar extends laterally between and isslidably connected to the extension members at the top of the framesection to provide lateral stability and to serve as an anchor point fordiagonal braces to the extension members. Jack screws are disposed onthe ends'of the extension members and are provided'with loadbearingsleeves which fit radially over the jack staffs and inner stabilizingshafts which extend telescopically into the jack staffs and are of alength greater than the length of the threaded portion of the jackstaff.

2 Claims, 11 Drawing Figures SHORING JACK This application'is adivisional of Ser. No. 65,137, filed Aug. 19, 1970.

This invention relates to shoring systems and the like and particularlyto stabilizing structures for such systerns.

Shoring systems are made up of vertically stacked frame sections atleast the upper ends of which are vertically adjustable either by meansof telescopic sections, jack screws, or both. A primary consideration inthe design of such apparatus is lateral stability and various bracingtechniques have been devised to provide such stability. Many suchtechniques, however, require that the equipment owner stock a largeinventory of different sized parts such as braces and frames so thatadequate stability can be provided in every shoring systemconfiguration.

In accordance with the present invention, a shoring system is providedwhich features high lateral stability and a reduction in the number ofdifferent parts to be stocked. In general, this is accomplished byproviding standardized bracing means for the extendable portion of ashoring system to eliminate the need for diagonal braces of manydifferent lengths between the uprights of the frames and the extendablemembers.

In a first form the invention comprises at least one frame sectionhaving hollow uprights, extension members telescopically extendablerelative to the uprights,

and a frame brace bar slidably connected to and extending between theextension members at the telescopic junction thereof with the uprights.This frame brace bar provides lateral stability between the extensionmembers, secures the extension members in the selected degree ofextension, and, in a specific form, carries means by which standardizeddiagonal brace bars can be secured to the extended telescopic extensionmembers.

Another feature of the subject invention is the provision of jack screwson one or both ends of the shoring system to provide a relatively largerange of infinitely variable height adjustments. In general, this isaccomplished by providing a hollow jack staff having a threaded portionwhich may be made relatively long, if desired, a threaded nut on thethreaded portion for vertical travel thereover, a load-bearing sleevebearing against the nut and extending over the staff to the end thereof,and an internal shaft which is fixed to the sleeve but extendsvertically into the staff a distance greater than the length of thethreaded section. This shaft extendsinternally of the jack staff andcarries no tension or compression loads but provides lateral stabilityfor the extended jack screw, thus, permitting exceptional extensionthereof if desired.

Other features and advantages of the invention will be described hereinincluding the matching or mating of full and half-size frame sections atlaterally opposite sides of a shoring tower, the following specificationto be taken with the accompanying drawings of which:

FIG. 1 is a side view of a shoring system embodying the invention;

FIG. 2 is an end view of the shoring tower of FIG. 1;

FIG. 3 is a detailed view of a jack screw assembly employed in theshoring system of FIG. 1;

FIG. 4 is a plan view of a frame brace bar employed in the shoringsystem of FIG. 1;

FIG. 5 is a side view of a portion of the jack screw assembly of FIG. 3;

FIG. 6 is another side view of the jack screw assemy;

FIG. 7 is a sectional view through the jack screw assembly;

FIG. 8 is a sectional view through the frame brace bar;

FIG. 9 is another sectional view through the jack screw assembly;

FIG. 10 is a plan view of a horizontal brace bar; and,

FIG. 11 is a side view of another shoring system.

Referring now to FIGS. 1 and 2, there is shown a shoring system 10comprising a frame section 12 having a pair of hollow, parallel uprights14 and 16 joined by laterally extending tubular members l7, 18, 20, and22. The bottom ends of the uprights l4 and 16 are seated in base members24 and 26 which are adapted to rest on any reasonably flat surface.Telescopically disposed within the uprights l4 and 16 are extensionmembers 28 and 30 in the form of jack staffs having threaded upper endsand carrying jack screw assemblies 32 and 34, respectively. The jackscrew assembly 34 which is representative is described in greater detailwith reference to FIG. 3. i

A frame brace bar 36 is disposed between the extension members 28 and 30and slidably secured thereto to permit the extension members 28 and 30to be vertically adjusted relative to the uprights l4 and 16. As bettershown in FIG. 4, the frame brace bar 36 includes short tubular shorecollars which slidably surround the extension members 28 and 30 andwhich otherwise merely rest on top of upper terminal ends of theuprights 14 and 16. Frame brace bar 36 contains a central support member38 carrying studs 84 and 86, as better shown in FIG. 4, to receive andsecure diagonal brace bars 40 and 42 which extend between the supportmember 38 and the extensionn members 28 and 30, respectively. A thirdbrace bar 44 which is identical to the diagonal brace bars 40 and 42extends between the extension member 28 and 30 at the lower ends of thethreaded portions.

The brace bars 40, 42, and 44 are simply angle iron lengths of L-shapedcross-section having a plurality of spaced holes formed therein suchthat the bars may be secured to other shoring system elements by meansof studs which fit into the holes in the bars. It will be observed inFIG. 1 that while the spacings between holes in the jack staffs areuniform, the spacings between the holes in the diagonal brace barsgradually decrease from the ends toward the centers in accordance with atrigonometric function such that as the extension members 28 are loweredinto the uprights 14 causing the angle between the extension member 28and the diagonal brace bar 40, for example, to increase, the diagonalbrace bar 40 may still be secured to the support member 38 by means ofthe hole and stud arrangement. Uprights 14 and 16 are also provided witha plurality of inwardly extending studs 46 for the securement ofhorizontal brace bars, as shown in FIG. 1.

Referring now to FIG. 1, a side view of the shoring system 10 shows theframe 12 spaced oppositely from a pair of vertically stacked half-sizeframes 48 and 50 having an intermediate coupling pin 52 and a base 26.The half-size frame sections 48 and 50 are provided with a plurality ofvertically spaced studs 53 to receive the ends of tubular horizontalbrace bars 54 and 56 as well as diagonal, brace bars 58, 60, and 62,these brace bars again being made of angle iron stock. The horizontalbrace bars 54 and 56 are similarly provided with studs 63 which receivethe other ends of the diagonal brace bars 58, 60, and 62, as shown. Thediagonal brace bars 58, 60, and 62 are again identical to the brace bars40, 42, and 44 of FIG. 2.

The frame section 48 and 50 are each made up of a pair of uprightssimilar to uprights 14 and 16 of the frame 12 in FIG. 2 and each of theuprights of the upper frame section 50 is provided with a telescopicextension member 65 in the form of a threaded jack staff having an upperjack screw assembly 66. Diagonal brace bars 64 and 67 are connecteddiagonally between the horizontal brace bar 56 and the stud collars 104of the jack staffs 28 and 65, respectively, for lateral bracingpurposes. Again, the diagonal brace bars 64 and 67 are identical tobrace bars 58, 60, and 62 and all of the diagonal brace bars may,obviously, be interchanged in position with one another. Thetrigonometric function spacing of the holes in the diagonal brace bars64 and 67 again permits the diagonal brace bars to be connected betweenthe jack staffs 28 and 65 and the horizontal brace bar 56 in any of theheight adjustments provided by the various pin holes in the jack staffas previously described.

For illustrative purposes, the dimensions of the shoring system elementsshown in FIGS. 1 and 2 may be approximately as follows:

The height of a full-size frame inches.

The width of a frame section is 4 feet.

The length of a diagonal brace bar is 4 feet.

The length of a horizontal brace bar shown in FIG. 1 is 8 feet but maybe any length required for frame spacing. I

The length of a jack stafi is 4 feet, 3 inches.

section is feet 11 The length of the threaded portion of the jack staffis 10 inches.

FIGS. 4 and 8 show the frame brace bar 36 in greater detail to include apair of elongated members 68 and 70 of L-shaped cross-section disposedin parallel and slightly spaced relation and secured such as by weldingat the opposite ends thereof to shore collars 72 and 74 the insidediameters of which are selected to be equal to that of the frame sectionuprights 14 and 16 of FIG.

1. The outside diameters of shore collars 72 and 74 may be larger ifdesired. At the center of the frame brace bar 36 is a rectangularsupport member 38 having a generally box shape and secured, such as bywelding, to the elongated frame brace bar members 68 and 70. Studs 84and 86 extend outwardly from opposite sides of the support member 38 andare in slightly staggered relationship with one another consideredaxially along the longitudinal axis of the frame base bar 36 to restrictthe connection of the diagonal brace bars and 42 to respective sides ofthe assembly of FIG. 2. Semicircular notches 76 and 78 are formed alongthe longitudinal axis of the tubular shore collar 72 on the left side ofthe frame brace bar as shown in FIG. 4 to receive shore pins whichextend through the holes in the jack staff 28, as shown in FIG. 1, forvertical adjust-- ment purposes. Similar notches 80 and 82 are formed inthe right hand tubular shore collar 74 of the frame brace bar 36, asshown in FIG. 4.

Referring now to FIGS. 3, 5, 6, 7, and 9, the details of the jack screwassembly 34 are shown in detail, it being understood the jack screwassembly 34 is representative of all of the jack screw assemblies shownin the drawings of FIGS. 1 and 2 and further that such similar jackscrew assemblies may be employed on the bottom of the shoring systemshown therein for accommodation of nonlevel support terrain.

Jack screw assembly 34 comprises the elongated, hollow, tubular jackstaff 30 having a threaded upper portion and a plurality of verticallyspaced holes 92 formed therein. An annular nut 94 having internalthreads is disposed on the threaded portion 90 of the jack staff 30 suchthat rotation of the nut 94 causes vertical travel thereof relative tothe jack screw. A pair of handles 96 which project radially outwardlyfrom the nut 94 are provided for manual manipulation. A loadbearingsleeve 98 fits over and coaxial with the threaded portion 90 of the jackstaff 30 and is of a length approximately equal to the distance betweenthe upper surface of the nut 94 and the end of the threaded portion 90,as shown in FIG. 3. Sleeve 98 rests on the upper end surface of the nut94 and, thus, is caused to move vertically relative to the jack staff 30along with the nut 94. Lugs may be provided on the nut to maintain thesleeve 98 in the centered position, if desired.

The upper end of the sleeve 98 is secured, such as by welding, to a flatplate 100 which provides a loadbearing surface at the upper end of thejack screw assembly. The center of the plate is further secured such asby welding to a solid shaft 102 which fits telescopically within thejack stafi" 30 and is of a length which is considerably longer than thelength of the threaded portion 90 of the jack staff 30. The solid shaft102 carries no compressive or tension forces when the plate 100 isloaded but serves to provide lateral stability in the jack screwassembly 34 particularly when the loadbearing sleeve 98 is fullyextended.

To define the lower most position of the nut 94 relative to the jackstaff 30 and also to provide a secure position for the securement ofdiagonal brace bars, a stud collar 104 is welded to the jack staff 30 soas to just abut the nut 94 when the nut is in the lowermost position.Stud collar 104 carries two laterally extending studs 106 and 107 toreceive the diagonal brace bars 40 and 44 for example, as shown in FIG.2 and brace bars 64 and 67, as shown in FIG. 1. An additional pin at aposition 90 from the first pin 106 is also provided to receive thediagonal brace bar 67 for example, as

shown in FIG. 1.

Means are provided in the jack screw assembly of FIGS. 5 and 6 forpreventing the load-bearing sleeve and the plate 100 from sliding offinadvertently from the jack staff 30. This antiremoval means comprises apair of L-shaped fingers 110 which are secured to and project verticallyupwardly from the nut 94. The inwardly projecting ends of the fingers110 are closely spaced relative to diametrically opposite points on theload-bearing sleeve 98, as shown in FIG. 6. A first set of lugs 112 isdisposed on the bottom end of the sleeve 98, as shown in FIG. 5, atdiametrically opposite positions and the second set of lugs 114 isspaced upwardly therefrom and at a 90 rotational position from the firstset of lugs 112. Accordingly, the upper lugs 114 interfere first withthe inwardly projecting ends of the fingers 110 and require a 90rotation of the sleeve 98 before the first increment of axial removaldisplacement is permitted. At this time the second set of lugs 112interferes with the inwardly projecting ends of the fingers 110 andanother 90 of rotation is required before removal can be completed.

1n a typical example of useage two frames of the same size or afull-size frame section 12 and two half-size frame sections 48 and 50are assembled together by means of horizontal brace bars 54 and 56 toform a four-legged rectangular shoring tower, as best shown in FIG. 1.Additional four-legged assemblies may be disposed on top of one anotheruntil the proper height is reached. At the top of the uppermost framesection, a jack staff 30 is telescopically disposed into each of theuprights after first having disposed a frame brace bar 36 between theuprights of the frame section. The jack staff slides through first thetubular shore collar 72 at the outer end of the frame brace bar 36 andthen telescopically through the hollow tubular portion of the upright12. A shore pin is inserted through the hole 92 in the jack stafiwhenever the proper height adjustment has been reached. Diagonal bracebars 64, 53, 60, 62, 40, 42, and 44 are placed in position by means ofthe studs on the various elements and the holes in the diagonal bracebars. The jack screw assemblies 34 are then adjusted to the properheight, the internal shafts 1112 providing lateral stabilityirrespective of the height ad- 7 justment of the jack screw assembly.

FIG. is a plan view of a horizontal brace bar 56 similar to but shorterthan the horizontal brace bar 56 of FIG. 1. The bar 56' is preferablymade from tubular stock so as to be substantially rigid and having flatend portions 116. Holes are formed in end portions'116 to accept studsfor connection between frames as shown in FIG. 11. Studs 113 and 120 aredisposed adjacent opposite ends of bar 56' and extend in oppositedirections to secure diagonal brace bars to opposite sides thereof. Inaddition, studs 122 and 123 are disposed centrally of bar 56', extendingin opposite directions and slightly longitudinally offset for reasons tobe described.

Referring to FIG. 11, a shoring system 124 is shown to comprise spacedparallel frame sections 126 and 127 of equal height. The sections 126and 127 are interconnected adjacent the upper ends thereof by thehorizontal brace bar 56 and adjacent the lower ends thereof by adiagonal brace bar 128. Suitable studs are provided on the frame sectionuprights as was the case in FIG. 1.

Resting on the upper ends of frame sections 126 and 127 are shorecollars 130 and 131 which cooperate with shore pins 132 and 133 tosecure extension members 134 and 135 telescopically within the uprightsof the frame sections at the desired heights. Jack screw assemblies 34'and 34" are disposed on the upper ends of the extension members 134 and135 and are of the type illustrated in FIG. 3. Stud collars 136 and 137are welded to extension members 134 and 135 and carry studs 138 and 139,respectively.

For bracing purposes, diagonal brace bars 140 and 142 are connectedbetween the horizontaL brace bar 56 and the stud collars 136 and 137,respectively. Additional diagonal brace bars 144 and 146 are connectedbetween horizontal brace bar 56' and the uprights of frame sections 126and 127, respectively. Diagonal brace bar 140 is connected to therear-facing center stud 122 of horizontal brace bar 56' while diagonalbrace bar 142 is connected to the front-facing stud 123. Because of theoffset between the studs 122 and 123, the spacing between stud collar137 and stud 123 is such as to accept a diagonal brace bar 142 whereasthe spacing between stud collar 136 and stud 123 will not accept thediagonal bar. This exclusive bar position connector design precludes theattachment of the diagonal brace bars 140, 142, 144, and 146 in such anarrangement as to produce mechanical conflict between the diagonal bracebars as the extension members 134 and are lowered.

To clarify this point, it can be seen that in the position of FIG. 11,diagonal brace bars 142 and 146 cannot be connected on the same side ofhorizontal brace bar 56 or they would lie in the same vertical plane andconflict. In the fully raised configuration of members 134 and 135 thebars would not conflict, but the mistake would be realized if it becamenecessary to lower and rebrace the extension members. The stud offsetprecludes this misconnection in the first instance. The offset alsoappears between studs 84 and 86 for uniformity. The length of diagonalbrace bar 142 is such that as member 135 is raised, the lower end of bar142 describes and are which at all points is vertically clear of bar 144so as to avoidconflict. Again, bars 140, 142, 144, and 146 are allidentical to each other and to bars 40, 42, and 44 of FIG. 2.

It is to be'understood that the foregoing description is illustrative incharacter and is not to be construed in a limiting sense.

I claim:

1. A jack screw assembly for use in a shoring system comprising a hollowjack staff having a threaded portion, a nut on the threaded portion forvertical travel thereover, a load-bearing sleeve bearing against thenut, and extending over the jack staff to the end thereof, and aninternal shaft fixed to the sleeve but extending vertically into thejack staff a distance greater than the length of the threaded portion.

2. Apparatus as defined in claim 1 including means to prevent axialdisplacement of the sleeve and shaft relative to the nut except when thesleeve and shaft ocangular position.

